SCHOTT solutions no. 2/2014 > Pharmaceutical Packaging

Prefillable syringes are manufactured out of many different materials. This increases the likelihood of interactions occurring between a medication and components of the syringe during shelf life. syriQTM InJentle reduces this risk. Photo: SCHOTT/L&K

Safer packaging for sensitive drugs

Interaction between a drug and its primary packaging is currently one of the most important topics for the pharmaceutical industry. This can mainly be attributed to the already high and growing demand for innovative biotech drugs which are generally administered by injection. Pre-filled syringes (PFS) make injections easier and safer for both doctors and patients. When stored in a PFS, however, the drug comes into contact with more materials than in other types of packaging. After all, the system includes the glass or polymer barrel, needle, needle glue, needle shield or closure system, plunger, and silicone oil that is used as a lubricant inside of the syringe barrel. ”With so many materials coming into contact with the drug, the chances of an interaction between the drug and syringe components during shelf life increase significantly, and the risk is even higher for sensitive biotech drugs,” explains Anil-Kumar Busimi, Head of Global Product Management for the Syringe Business at SCHOTT.

Interactions between drugs and pharmaceutical packaging currently represent one of the most important topics for the pharmaceutical industry – particularly with respect to biotech medications. Photo: SCHOTT

New design for prefillable syringes

In response to these challenges, the company has now developed a new PFS design that goes by the brand name syriQTM InJentle. This innovative PFS consists of a glass barrel with a special design and an integrated needle system consisting of a fluid path made of a rubber bung, a needle and a tamper evident needle shield. A special ’pinch seal’ of the rubber bung keeps the fluid path closed during storage and prevents the drug from coming into contact with the metal needle or the adhesive.

This special design of the glass barrel also eliminates the use of a tungsten pin during the glass forming process and thus rules out any interaction of sensitive drugs with tungsten. Studies have shown that tungsten residues can interact with sensitive biological drugs and lead to protein aggregation. This not only destabilizes the pharmaceutical formulation, but also possibly causes an undesirable immune response from the patient after the injection.

syriQTM InJentle syringes are free of tungsten (1) and protect sensitive medicines from interacting with metal needles or glues during storage (2). The silicone is baked on to allow the plunger to slide more smoothly. This reduces the free silicone and the respective particles (3). A tamper-evident closure allows doctors and patients to recognize whether a syringe is new or not (4). The needle does not come into contact with the needle shield and is therefore protected and stays sharp (5). Source: SCHOTT

Yet another improvement with syriQTM InJentle is the lubrication of the barrel. Generally, silicone oil is used to lubricate the inside of the syringe barrel to ensure smooth injection. But, silicone oil can be a source for particles which could alter sensitive proteins under certain conditions. syriQTM InJentle features a glass barrel that has ”baked-on” silicone. This results in less free silicone and significantly lower particles without compromising the functionality of PFS.

Furthermore, the needle shield has a tamper-evident closure. Doctors and patients can thus immediately tell whether a syringe has already been used or not. In addition, the needle does not come into contact with the inside surface of the needle shield thus protecting the sharpness of the needle. syriQTM InJentle PFS can be offered with thin needles up to 32 gauge that reduce the pain of an injection for the patient. ”With our syriQTM InJentle syringe, the drug comes into contact with the same materials as it does in a vial – glass and rubber,” Busimi concludes. ”This is important for pharmaceutical companies that are interested in switching from vials to syringes. Our solution makes the change much easier. In addition, we ship our products in standard nests and tubs for filling on conventional filling lines,” he says.